| 摘要 |
PURPOSE:To secure a size compensator capable of performing size compensation in a short time as well as in high accuracy, by drilling an H-beam or the like having a web and a flange being formed opposite to both sides of the web at equal distances from the center of thickness in the web to both sides of the flange. CONSTITUTION:When drilling takes place to an H-beam 2 which sets one end of a flange 2b down to a supporting zero point 0, first a conact member 19 in a transfer part 18 of a size compensator 17 is made to come into contact with a plane surface on a web 2a of the H-beam 2. Movement of the transfer part 18 is transmitted to a rotary encoder 25 by both of a rack 20 and a pinion 24 whereby sizes B and B' are detected. These sizes B and B' are inputted into an operation device 28 together with those of length H/2 of 1/2 of the flange 2b, thickness W/2 of 1/2 of the web 2a, a bore pitch P and a desired value D designated in size from the supporting zero point 0 of the flange 2b, etc. And, the desired value corresponding to the drilling position of the flange 2b is calculated, thereby controlling a cylinder, and a drill unit 10 is driven for operation. |
